University of auckland, Cary Institute
University of auckland
Manaaki Whenua - Landcare Research
2025-11-17
Proxy data are the product of multiple sources of uncertainty
Virtual ecology (Zurell et al. 2010)
Proxy system modelling (Evans et al. 2013)
Pseudoproxy experiments (Mann and Rutherford 2002)
Other key refs:
Virtual ecology is a framework for assessing sampling and analytical methods in simulation consisting of:
an ecological model that generates synthetic data
1a. a degradation model
a simulated observational process (a sampling model) that samples the synthetic data
an analytical process or statistical model applied to both sets of data
an assessment of the results
Known drivers and responses
Known environmental and observational processes
Advantage of benchmark/control data
Advantage of replication
Able to systematically introduce uncertainty
Sampled data with no benchmark/control
Advantage of being reality
The process by which environmental change is recorded as an observable signal in an archive:
Borrowing the term “pseudoproxies” from climatology:
Let’s follow a singe replicate case-study
We set out to:
Ok, now we have generated the data, let’s analyse it. Two analyses:
Demonstrating two scenarios with different driving environments.
Pervious slides followed:
Each replicate results in 1210 datasets from the ‘error-free’ to the most uncertain 😱.
Across replicates for each of the 1210 datasets:
extract features from the FI and PrC
calculate the distance between each dataset from the ‘error-free’ to the most uncertain
make cool visulisations!